“…They have been originally introduced in the sine-Gordon equation [1], but they can also be found in other scenarios, controlled by the modified Korteweg-de Vries equation [2], the Davey-Stewartson [3] and the nonlinear Schrödinger equation [4]. In various physical systems, which are well described by nonlinear equations, breathers directly affect their electronic, magnetic, optical, vibrational and transport properties, such as in Josephson superconducting junctions [5,6], charge density wave systems [7], 4-methyl-pyridine crystals [8], metallic nanoparticles [9], conjugated polymers [10], micromechanical oscillator arrays [11], antiferromagnetic Heisenberg chains [12,13], and semiconductor quantum wells [14].…”